微带型光导开关的电压转换效率

采用微带测试电路对光导开关电压转换效率进行了测试。依据传输线理论,考虑微带传输电路的端点反射,计算给出了光导开关导通电阻不为0的情况下,微带测试电路电压转换效率的解析结果。计算表明:对窄脉宽的线性电脉冲输出,电压转换效率将小于50%;对lock-on模式下的宽脉冲输出,电压转换效率可以超过50%,在理想情况下达到100%;在临界状态下,形成双峰电脉冲输出。结果表明,存在端点反射且光导开关产生电脉冲脉宽达到一定值时,微带线可以起到倍压传输线的作用。     

基于相关分析的LED路灯光强分布测试步距角优化研究

优化LED路灯光强分布测试系统的测试步距角可以较大程度地提高LED路灯测试的效率。选择不同的测试步距角对LED路灯的光强分布进行测试,将1°测试步距角所测得的路灯光强分布视为真值,采用相关分析的方法研究在较大步距角下所测得的路灯光强分布与真值之间的近似程度。研究结果显示,当相关系数要求在98%左右时,可以选择15°测试步距角对LED路灯的光强分布进行测试,相对于真值测试,在此步距下LED路灯的测试时间减少了98%以上,极大地提高了测试效率。     

用复势函数计算特殊边界形状的静态场问题

通过复势函数计算出了同轴圆弧柱形电容器及非平行板电容器的电容、场强和薄金属弧片中的电导、电势.     

第十三届全国光学测试学术交流会第一轮征文通知

受中国光学学会委托,中国光学学会光学测试专业委员会定于2010年7月在武汉召开第十三届全国光学测试学术交流会．本届会议由武汉大学和湖北省光学学会承办。     

Assessing total differences variations in color,for effective samples having coarseness,and glint

Effect coatings have the unique property of large change of appearance under different viewing conditions. This results in quality control problems of related products. In this letter, samples of metallic panels with effect coatings are visually assessed and measured. Based on experimental results, we propose formulae to predict precisely the total differences of effective samples in terms of variations in color, coarseness, and glint. Under diffused illumination, the total difference formula includes color difference and coarseness difference. Under directional illumination, the total difference formula includes color difference and glint difference.     

Similarity Solutions for Generalized Variable Coefficients Zakharov-Kuznetsov Equation under Some Integrability Conditions

In this paper, the symmetry method has been carried over to the generalized variable coefficients Zakharov- Kuznetsov equation. The infinitesimal symmetries and the optimal system are deduced and from this optimal system seven basic fields are determined, and for every vector field in the optimal system the admissible forms of the coefficients are found and this also leads us to transform the given equation into partial differential equations in two variables. After using some referenced transformations the mentioned partial differential equations eventually reduce to ordinary differential equations. The search for solutions to those equations has yielded many exact solutions in most cases.     

B→K0^＊（1430）η（＇） decays in the pQCD approach

Based on the assumption of two-quark structure of the scalar meson K0^＊（1430）, we calculate the CP-averaged branching ratios for B→K0^＊（1430）η（＇） decays in the framework of the perturbative QCD （pQCD） approach here. We perform the evaluations in two scenarios for the scalar meson spectrum. We find that： （a） the pQCD predictions for Br（B→K0^＊（1430）η（＇）） which are about 10^-5 10^-6, basically agree with the data within large theoretical uncertainty; （b） the agreement between the pQCD predictions and the data in Scenario Ⅰ is better than that in Scenario Ⅱ, which can be tested by the forthcoming LHC experiments; （c） the annihilation contributions play an important role for these considered decays.     

Strange quark dynamics on hot dense matter under the extreme condition

Production and properties of φ-meson under the extreme hot dense matter which is formed in Au ＋ Au collisions at RHIC energy have been briefly reviewed.The issues are focused on transverse momentum （p T ） spectra of φ,elliptic flow of φ,nuclear modification factor of φ,the ratio of Ω（p T ）/φ（p T ） versus p T,the ratio of Ω（p T /3）/φ（p T /2） versus p T /n q,spin alignment of φ and the enhancement of φ etc.These observables give the significant information of the strange quark dynamics in hot dense matter under the extreme condition.     

Radiative leptonic decay Bc^-→τ^vτ^-γ in the standard model and the two-Higgs-doublet model

We analyze the radiative leptonic Bc decay Bc^-→τ^vτ^-γ in the Standard Model and the two- Higgs-doublet model using the non-relativistic constituent quark model. The results confirm that this channel is experimentally promising in view of the large number of Bc mesons which are expected to be produced at future hadron facilities. We also find that this decay is sensitive to the parameters of the two-Higgs-doublet model, and it can be tested in future experiments.     

Control system for the CSNS ion source test stand

A penning plasma surface H- ion source test stand for the CSNS has just been constructed at the IHEP. In order to achieve a safe and reliable system, nearly all devices of the ion source are designed to have the capability of both local and remote operation function. The control system consists of PLCs and EPICS real-time software tools separately serving device control and monitoring, PLC integration and OPI support. This paper summarizes the hardware and software implementation satisfying the requirements of the ion source control system.